Disperser for powders



July 18, 1961 Filed March 26, 1959 WEIGHT PERCENT Jol'- F. FOWLERDISPERSER FOR POWDERS I I 93% I i l I 4 Sheets-Sheet 1L WEIGHT PERCENTJo 11.1215141515 .wjiqz'om zzeauz DISPERSER FOR POWDERS Filed March 26,1959 4 Sheets-Sheet 2 July 18, 1961 F, FOWLER 2,992,645

DISPERSER FOR POWDERS Filed March 26, 1959 4 Sheets-Sheet 5 July 18,1961 F, FOWLER 2,992,645

DISPERSER FOR POWDERS Filed March 26, 1959 4 Sheets-Sheet 4 l 6- M .JQ fL7/(7? l l* y l l I #y 1| J0 62 IL 6] 65 V il| @1f ,76 65 f J5 f 29 50United States This invention is concerned with novel apparatus andmethods of yadministering a medicament or drug in the form of ahomogeneous ultra iine powder which can be deposited in the deeper partsof the lung following inhala tion of air or a gas containing the saidultra ne powder in suspension.

For a full understanding of the invention which is described hereinafterin detail, it should be recalled that the human respiratory systemcommences with a single large diameter tube and after many bifurcationsterminates in many thousands of very small diameter tubes (approximately0.6 mm. bore). The large primary tubes also have appreciable length,whereas the terminal subdivisions are quite short in length. On theother hand, the larger tubes are few in number and have `a very smalltotal surface area (of wall) compared to the very large total surfacearea of the thousands of small tubes. The Various types of tubes whichoccur Iare described by terms such as: main bronchi, primary bronchi,secondary bronchi, tertiary bronchi, bronchioles, respiratorybronchioles, alveolar ducts yand alveolar sacs.

This invention is chiey concerned with apparatus for the application ofsome powders containing drugs to the surfaces of lthe tubes classed asbronchioles and respiratory bronchioles, which fare the smaller and moredistal parts of the branched system, with a minimum proportion depositedin the trachea and main bronchi alveolar ducts and sa, either for thetreatment of local disease, or for the purpose of obtaining rapid andcomplete absorption of the drug into the blood stream.

lt has been variously reported and is well accepted that particles ofsolid, or droplets of liquid, with a diameter exceeding microns cannotbe carried by inspired air in any significant degree beyond thesecondary or tertiary bronchi. This may be looked upon as a quitereliable natural defense mechanism against invasion of the deeper andeective parts of the `lung by foreign matter in the air such as dust,bacteria, etc. It is also fairly well established that particles of dustor smoke with a particle size diameter of less than l micron will veryreadily pass along the tubes to the most distant parts of the lung,namely the alveolar ducts `and sacs, but the smaller particles in thisrange are probably not deposited at all, but return with the exhaledair.

This invention advisably uses a homogeneous ultra tine powder in whichthe particles are mutually non-adherent in which at least a majorproportion, and advisably about two thirds of the powder, by weight iscomposed of particles having a diameter between 2 and 6 microns.Approximately 80% by weight should preferably be between these limitswith the peak of the weight distribution curve approximating the 3micron size. The powder should contain substantially no particles largerthan 10 microns, or preferably no larger than 9 microns, and any eventonly a very minute proportion by weight of the particles should be over10 microns in size, and only a negligible proportion by weight of theparticles should be smaller than l micron. In any case, the proportionby Weight below 2 microns should be less than 20%, Or preferably lessthan 10% by weight, so that the product is substantially free fromparticles appreciably smaller than 2 microns.

The advantage of employing a homogeneous powder arent l" ice of thistype may be demonstrated quantitatively in several ways. For example, itcan readily be shown that when the powder of this invention is inhaledas on a gas or air supported stream, the dosage required to produce agiven `desired result may be reduced by as much as -95 with the finehomogeneous particles as compared with, for example, a powder of thesoca1led 300 mesh size, i.e., as obtained by grinding `and sievingthrough a 300 mesh per inch sieve administered in the same way.

The following table shows quantitatively the theoretical distribution ofan insuiiiation powder through the various areas of the bronchial systemwhen the particles are of various sizes. It will be noted that withparticles of 3 micron diameter the bronchioles and respiratorybronchioles may be expected to receive and retain 46% by weight of thematerial as compared to only 11% in the case of a 1 micron powder andonly 10% for a powder composed of l0 micron particles.

Table showing percentage by weight of a powder of speced particle sizewhich would be expected to be deposited in the different regions of thelung In the accompanying drawings FIGURE 1 shows the panticle sizedistribution by weight of a typical known powder classed as passing a300 mesh sieve, while FIG- URE Z shows the corresponding distribution ofa preferred powder in accordance with the invention.

Although the tine powders of mutually nonadherent particles of 2 to 6microns can be administered by the use of `known procedures and withexisting devices, it is considered that all of the prior art methods andapparatuses have serious deiiciencies. For proper administration ofthese powders they should be thoroughly dispersed so that each particleis separately suspended in the inspired air or gas (oxygen) in order toobtain the desired effect. Not only must the powders `be properlysuspended, but they must be administered only during inhalation, and notduring exhalation or when a person is momentarily holding his breath,for the particles to be drawn in suiiiciently to reach the desiredrespiratory areas.

There are, accordingly, provided novel dispersers for administeringthese powders, as well as novel replaceable cartridges containing thepowders which can be used, if desired, in conjunction with the.dispersers.

The disperser broadly is comprised of a reservoir for a mass of iinelydivided particles, gas pressure means for supplying a gas under pressureto the reservoir and valve means for maintaining the gas under pressure,said valve means being responsive to external differential reduced gaspressure, such as caused by the inhalation of a person, to open thevalve so that the particles are propelled from the reservoir as a gassupported stream. The said valve may be located between the gas pressuremeans and the reservoir but advisably is located in an egress conduitleading from the reservoir so that said gas pressure means appliespressure inside the reservoir before 3 the valve is opened-in this wayimmediate expellation of powder from the reservoir is accomplished uponopening of the valve. In a further embodiment of the invention gas underpressure is not only supplied to the reservoir, but is also supplied toone or more ducts which direct a jet of this pressurized gas across thestream of particles emerging from the reservoir.

The reservoir may comprise any suitable container for the powders of asize and shape such that gas applied under pressure thereto can beexhausted from an egress hole in the container and transport the powderparticles as a gas-supported stream. The container can be an 'mtegralpart of the disperser but, advisably, is a replaceable cartridge whichcan be readily positioned in a cartridgereceiving receptacle provided inthe disperser.

Embodiments of the disperser will nowI be described in conjunction withthe attached drawings in which:

tFIG. 3 is a cross-sectional View in elevation of a cartridge;

FIG. 4 is a perspective view of the cartridge shown in section in FIG.3;

lFIG. 5 is an enlarged View of the lower portion of the cartridge shownin FIG. 3;

FIG. 6 is an elevational View partly in section of one embodiment of thedisperser;

FIG. 7 is an elevational view of another embodiment o-f the disperser;

FIG. 8 is a view of the disperser of FIG. 7 taken partly in section atthe line 8 8 thereof;

FIG. 9 is a View of a cartridge for use in conjunction with thedisperser of FIGS. 7 and 8; and

FIG. l() is an enlarged sectional View, ten times scale, of thecartridge receiving area of the disperser of FIG. 6 containing acartridge.

Referring rst to the disperser of FIG. 6, which is the preferred device,it will be seen that it comprises a squeeze bulb 10 with valve 11 whichlets in air but prevents its escape, and that the bulb is attached tocylindrical mouthpiece 12. The mouthpiece -12 is composed of three mainportions which are threaded together into a unitary structure which canbe disassembled readily. Forming part of the mouthpiece 12 is the base13v to which the bulb 10 is attached. Body 14 is threadably engaged at15 to the base 13, and at the other end is threadably engaged to thenozzle portion 2S.

The base section 13 contains axial hole 16 and cartridge receivingrecess 17 into which approximately the lower half of a powder-containingcartridge fits. The dotted lines I18 signify that grooves are provided:in the bottom and sides of the recess 17 so that air may pass aroundthe cartridge as well as go through it. To provide a tight seal betweenthe base section y13 and the body 14, flexible washer 19, as of rubber,is placed in the top of the body portion as shown. Shroud 20 is added toprotect the bulb throat 21 and bar its being removed inadvertently fromthe nipple 22 containing hole 16; the shroud also gives the device amore elegant appearance.

Body portion 14 is generally shaped like a cylindrical shell withinternal thread means 15 at the lower end and internal thread means 26at the upper end. Body 14, however, contains an inverted cup 27integrally formed -therewith by shoulder 28. The cup 27 is flared 29 atits mouth to facilitate entry of the upper part of a cartridge into thecup. It will be readily seen that cup 27 and recess 17 are coaxiallypositioned and of a size so that together they comprise a cartridgereceiving receptacle. The cup 27 contains grooves 18 in the walls andbottom `thereof which actas passages for air to pass around thecartridge. The cup 27 has orice 30 axially located therein and solocated as to be in line with and adjacent the egress hole of thecartridge so that the air or gas transported fine particles can beexpelled therethrough. The body 14 has side ports 31 which permit air toenter therein.

Nozzle 25 is threadably attached 26 to the body 14 and contains aninternal downwardly projecting cylindrical sleeve 40 having` throat 32spaced apart 33 from the outer Wall of the nozzle.

Located in `the body 14 is a piston 34 comprised of a disc 35, fromwhich cylindrical skirt 36 depends, and also from which cylindricalsleeve 37 projects upwardly 'm line with sleeve 40. The top of sleeve 37is castellated so that when it abuts the bottom of sleeve 40 it will notprevent the application of suctionin areas 33 and 41. The disc 35 has aflange 42 which extends outwardly beyond the skirt 36 so that whensuction is applied through throat 32 and in varea 41, yair will enterports 31 and apply pressure against the flange 42 and thus force thepiston upwardly. As the piston moves upwardly the bottom edge of skirt36 is raised permitting air to ilow therebeneath and into area '43 whereit combines with the yair-transported particles coming out orifice 30and facilitates dispersing the particles and transporting them throughholes 44 in the `disc portion 35 of the piston and through throat 32into the respiratory system of an inhaling person. Pad 45 is located inthe bottom of the disc 35 to provide a good seal of orifice 30` when thepiston is at rest. Spring means 46 extends around sleeves 37 and 40 andurges the piston away from the nozzle portion. The tension of the springis carefully selected so that it will maintain the piston down until aperson creates a suction, as by inhaling with the mouthpiece lin hismouth, in the area 41 after wh-ich atmospheric pressure forces thepiston upwardly by air entering ports 31.

The disperser is advisably made of nylon except for the bulb, washer andpad which can be rubber, while the spring may be steel.

Shown in FIGS. 3, 4, and 5 `are views of a cartridge 50 which can beused in the disperser of FIG. 6 and which tits in the receptacle formedof recess 17 and cup 27. The cartridge has `a cylindrical body portion51 having a tightly fitted cap 52. The cartridge has an internalcylindrical cavity tapered `at both ends into conical areas with the endportions of the cones adjacent the top and bottom ends of the cartridge.The tapered areas `assist `in the ejection of all of lthe contents inthe cartridge and thereby assure utilization of the entire dosage. Thebottom of the body portion is provided with a small opening 53,preferably about 1&4 of an inch in diameter. Cavity 56 is provided aspart of the `ingress hole to facllitate molding. This opening 53 (theingress opening) is for the linjection of air into the cartridge. Thecap 52 is provided with opening 54, preferably about 1/32 of an inch indiameter for ejection of the powder from the cartridge by means of theyair injected at the bottom. Ring 63 on the cap and ring 64 on the bodyportion 51 frictionaly fit in corresponding grooves to aid in holdingthe parts together. Adhesive sealing discs 55, as of polyethylene, are-applied to the ends of the cartridge to bar access of moisture to thepowder in the cartridge. These discs are removed before the cartridge isplaced in the disperser.

A typical cylindrical cartridge may be about 13 mm. long and labout: 8mm. in diameter with an air ingress hole of 0.20 to 0.25 mm. andacombination particle and air egress =hole of 0.8 to`1.0 mm. The ends ofthe cylinder in which the holes are located `are conically shapedinternally with the cone tops directed to the cartridge ends. The lairingress hole can have a wall length of about 0.25 mm. Iand the egresshole a wall length of about l mm.

The powder is packed lightly in these cartridges in such a manner `as tobe free-flowing in the air which is used to remove it, and yet isloosely aggregated so that the holes at either end of the cartridge aresmall eno-ugh to ensure that the powder does not flow out under ordinaryhandling conditions. Such cartridges are prefl erably moulded from aplastic material, such as polyethylene, which amongst other propertieshas that of preventing the passage of moisture vapor to a remarkabledegree and yas these very ne powders may be damaged in the case ofcertain drugs by moisture, this can be a marked advantage.

This apparatus serves at least ltwo functions, it disperses the powdercompletely into the inspired air and, secondly, it only releases thepowder when the patient is making a sutiiciently strong inspiratoryeffort.

Although lthe powders are composed of mutually nonadherent particles,they 'are of such `a smal-1 particle size that there is a considerabledegree of loose physical aggregation which may be due, in part, toelectrostatic forces. In order for each individual particle to beseparately suspended in the inspired air it is advisable that the streamof powder smoke removed from the cartridge be vigorously acted uponmechanically to break -up the loose physical aggregates. With this endin view, and yas shown in greatest `detail in FIG. 10, the rubber bulb,of approximately 60 `cc. capacity, delivers about 5G cc. of pressurizedair to duct 16. About of the pressurized air passes through thecartridge and transfers some ofthe powder into a small turbulent mixingchamber 61 just above the cartridge egress hole 54. About 90% of thepressurized air is permitted to by-pass the cartridge by means ofgrooves 18 which divide the air into two streams of `about 22 cc. eachwhich feed it to opposed jet ducts 62 and 63 from. which the air ispropelled with a violent turbulent -action upon the powder emenging:from the cartridge. The small mixing chamber yel is only about 11/2 mm.(1/16") diameter and 2 mm. long `and forms the lower part of the duct30. 'llhe air propelled completely dispersed particles are thenpropelled 'from `chamber `6l through duct 30 as `a 50 oc. quantity of avery concentrated powder smoke. The 50 cc. quantity of smoke is dilutedwith l to 25 Iliters of air which enters port 31 and passes throughholes 44 with the smoke.

When the patient commences to breathe in through the mouthpiece he findsthat only a very small quantity of `air can be obtained and hence he canvery quickly build up a strong suction in lthe apparatus. When thedegree of suction reaches a certain value the valve is triggered andAair flows into his lungs lat a rate of 2 or more liters per second. Thepatient is `able to maintain this rate of flow from between 0.5 and 1.0second `during which time he has inspired between l to 2.5 liters ofair. It is `during the iirst 0.3 second that the 50 cc. of concentratedpowder smoke is injected into the air ilowing during that period oftimei.e., into approximately 0.8 liter of air. It will be seen,therefore, that even in the case of -a severely disabled patient havinga small inspiration there will still be an appreciable amount of furtherair inspired after the end 4of the powder addition. 'l'his further helpsto ensure `that the 0.8 liter of air containing the powder istransferred into the deeper parts of the lung.

This device was found to be very satisfactory in practice. The eifectproduced is to cause the patient to make a strong inspiratory effortwithout at the same time filling his lungs prematurely with air and onlywhen he is making a suiiiciently strong effort can he get both the airand the dose of powder.

The disperser of FIG. 6 is preferred to that of FIGS. 7 and 8 since theformer requires less air intake to open the valve and is easier to cleansince the spring 46 is protected and out of the path of theair-transported particles. Furthermore, by having the atmosphere applypressure initially only against the lange 42 instead of the entire areaof the disc, it requires more suction to open the valve compared to thesuction necessary to maintain it open than in the device of FLGS. 7 and8 which, as a result, causes the powder to be inhaled more deeply.

The disperser as shown in FIG. 6 is about 2 times scale so that it willbe readily appreciated that the device is suitable for carrying by aperson in a coat pocket in order that the insulation powder can beself-administered at any location convenient to the patient, such as athome or his place of business.

A second embodiment of a disperser is shown in FIGS. 7 and 8 and acapsule for use in conjunction with the `disperser is shown in FIG. 9.

The disperser of FIGS. 7 and 8 has a mouthpiece 70 connected to bulb 71.The mouthpiece 70 has a cylindrical end section 72 through which anaxial duct 77 passes to the discharge oriiice. An intermediate sectionof said end section 72 is formed with two opposed parallel faces 73, thedisposition of which is chordal with respect to the cylindricalprojection of the end section 72. Between the faces 73 a socket recess79 for receiving cartridge 74 extends transversely so that the duct 77QG at lower part and 1/32" at top) opens into it. Beyond the socketrecess a nozzle 76 having hole 75 (1/s) is engaged with the mouth 78 ofthe bulb. The bore of hole 75 is on the same axial alignment as duct 77so as to open into the recess 79.

The socket recess 79 is generally cylindrical with one end fully openand sunk into one of said faces 73 with the other end partially narrowedor closed so as to leave a slot in the other face. The socket recess 79is stepped down in diameter 81 on the far side of the duct 77 and hole75.

The cartridge 74 for mounting in the recess is formed externally as thesocket recess except that the area 8S of the cartridge is smaller thanthe the near side 89 (biggest diameter in the socket) of said duct 77and hole 75 to thereby create an annular passage 83, of general ringshape, between the two steps 81 and 90 and around the cartridge. Theorifices S5 and 86 in the cartridge are positioned to register with thehole 75 and duct 77 respectively and to be located in the annularpassage 83. By making the depth of the steps and the distance betweenthem such that the resulting cross-sectional area is about four andone-half times as large as orifice 85 (%4) or 86 (1/32) whichever isbigger, roughly nine times as much air will be diverted around thecapsule as can pass through it in a certain period.

In order to ensure a tight t of the cartridge within the socket recess,the mating surfaces ot both, outside the passage zone between the steps,may be tapered slightly towards their far or inner ends. The near orouter end of the cartridge is flanged S7 for engagement within the sunkface opening of the recess. The lling mouth of the cartridge is providedwith a suitable stopper plug 91 externally yformed with a button bywhich the capsule can be readily pressed home into the recess. The faror inner end of the cartridge is formed with a projecting key adapted tofit and project through the slot in the far end of the recess toproperly align the orifices with hole 7S and duct 77.

The cartridges can be supplied for use in the disperser, each removablymounted, in individual tubular sheaths which may also be of plastic and,can, if desired, be combined to any required number into a plate withthe sheaths projecting as sockets from its face. The orifices of eachcartridge are thus kept sealed, by the wall of such sheath or socket,and the contents protected from deterioration and, what is particularlyimportant with very iine powders, from dampness such as might causecaking.

The mouthpiece is provided with a tubular sleeve 91 axially projectingaround the discharge duct, the inner end of which sleeve may bedetachably secured to a shouldered seating 99 on said end section.Immediately adjacent the end of the latter, the sleeve has air intakeopenings 92. Loosely fitting within the sleeve is a disc 93 serving bothas a piston hafiie and as a valve member, for which last mentionedpurpose said disc is provided with a central sealing pad 94 whichnormally seats against and closes the discharge duct 77. By disposingthis duct at the tip of the axial conical projection 95 of the body,said disc is maintained clear of said zone of sleeve openings on theupper or suction side of the intake openings. The disc is urgeddownwardly into seating engagement with the duct by a coil compressionspring 96 of about the same diameter as the disc itself, which springmay be anchored just within the open end of the sleeve 91 and saidspring and disc can, if desired, be formed integrally with the sleeve asa single moulding. The strength of the spring is such that it allows thedisc to be lifted from the discharge duct by an air current drawn, byappropriate suction at the nozzle 97 end of the sleeve as by placing themouthpiece in the mouth and inhaling in through the zone of openings andaround the edge of the disc, but on the other hand prevents the latterfrom being raised without, or unassisted by, such suction, merely bypressure obtainable by means of the collapsible bulb acting over thesmall cross-sectional area of the orifice. The sleeve is suitably nishedolif as a mouthpiece by iitting its open end with a supplementary domedannulus or nozzle 97.

Valve 11 is the same as in FIG. 6.

The valve means of the disperser of FIGS. 7 and 8 prevents emission ofair-supported powder through duct 77, even though the bulb 71 issqueezed, until a suicient air current is simultaneously drawn inthrough the mouthpiece, thus ensuring against waste of powder as wouldtake place if exhalation, or no inhalation, was taking place. The valvemeans does this by being diierentially operated in the sense that itpresents an area to the lifting influence of the inhaled air currentwhich is large in comparison with the very small area it presents forlifting by the air pressure at said orifice. The disc functions as aloosely fitted piston within the mouthpiece and is adapted normally tobear against the orice through the sealing pad under the influence ofgravity and/or the spring, with a force which the opposed air pressureis unable to overcome by itself. Conscious synchronism betweeninhalation and discharge of the powder-bearing air is thus not required.The valve cannot be opened under the sole influence of pressure in thebulb but can be opened by a predetermined degree of suction caused bythe drawing in of air through the mouthpiece.

Various changes and modifications of the invention can be made and, tothe extent that such variations incorporate the spirit of thisinvention, they are intended to be included within the scope of theappended claims.

What is claimed is:

1. A hand-transportable disperser for administering fine powderedmaterials to a human comprising a mouthpiece, a reservoir for nelydivided particles communicating with the mouthpiece and having ingressand egress holes therein, a exible squeeze bulb for applying air underpressure to the reservoir interior via the ingress hole, a valvecomprising a piston, a first side of which has means to seal exit feedmeans communicating from the bulb for maintaining a superatmospheric airpressure in the bulb, the second and opposing side of said pistoncommunicating with a nozzle in the mouthpiece, said rst side of thepiston being partially open to atmospheric pressure so that when themouthpiece is placed in a humans mouth who inhales, sub-atmosphericpressure is created in the nozzle and the piston is raised byatmospheric pressure applied against the first side thereby opening thevalve so that the air under pressure in the bulb blows through theingress hole and out the egress hole to form an air-supported stream ofparticles propelled out the nozzle and into the respiratory system.

2. A disperser for administering ne powdered materials to a humancomprising a mouthpiece portion essentially hollow internally and havinga closed lower end portion and an open upper nozzle portion, a duct inthe closed end portion leading at the upper end from the hollow portionof the mouthpiece to air pressure means at the lower end for supplyingair at supra-atmospheric pressure to the duct, a reservoir for finelydivided particles located between the ends of the duct and communicatingtherewith by ingress and egress holes, a valve comprising a pistonslidably mounted inside the mouthpiece urged by spring means intosealing relationship with the upper end of the duct, port hole means inthe mouthpiece leading to an open area beneath the piston so as to applyatmospheric pressure ag-ainst the bottom of the piston, said springexerting pressure adequate to maintain the piston in duct-sealingrelationship when air pressure is applied in the duct with said springexerting substantially less than atmospheric pressure against the pistonso that a human, upon inhaling with the mouthpiece nozzle in his mouth,lowers the air pressure above the piston sufficiently for atmosphericpressure applied on the lower side of the piston to overcome the springpressure and displace the piston out of sealing relationship with theduct thereby letting the air pressure means blow air through thereservoir and create a stream of air-supported particles which isexhausted through the nozzle and inhaled into the respiratory system.

3. A disperser for administering fine powdered materials to a humancomprising a mouthpiece portion essentially hollow internally and havinga closed lower end portion and an open upper nozzle portion, a duct inthe closed end portion leading at the upper end from the hollow portionof the mouthpiece to air pressure means for supplying air atsupra-atmospheric pressure to the lower end of the duct, a reservoir forfinely divided particles located between the ends of the duct andcommunieating therewith by ingress and egress holes, a valve comprisinga piston slidably mounted inside the mouthpiece urged by spring meansinto sealing relationship with the upper end of the duct, said pistonhaving a downwardly projecting skirt spaced away from the mouthpieceinternal wall and extending into substantially sealing position with theinside of the closed end portion of the mouthpiece thereby forming anopen area between the mouthpiece wall and the skirt wall, port holemeans in the mouthpiece leading from the atmosphere to the open area soas to apply atmospheric pressure against a minor portion of the lowerside of the piston when the piston is in sealing relationship with theduct, said piston having conduit means therethrough leading from thearea surrounded by the skirt walls to the mouthpiece nozzle portion, thespring exerting pressure adequate to maintain the piston in duct-sealingrelationship when supra-atmospheric pressure is applied in the duct to apredetermined pressure, said spring exerting substantially less thanatmospheric pressure against the piston so that a human, upon inhalingwith the mouthpiece nozzle in his mouth, lowers the air pressure abovethe piston suiciently for atmospheric pressure applied on the said minorportion of the lower side of the piston to overcome the spring pressure,displace the piston out of sealing relationship with the duct anddisplace the skirt from sealing contact with the closed portion of themouthpiece thereby permitting air to pass from the open area to the areasurrounded by the skirt walls so that atmospheric pressure is applied tosubstantially the entire bottom of the piston, and the air which goesthrough the conduit means in the piston further disperses the stream ofair-supported particles which is created when air under pressure blowsthrough the powder reservoir and out the duct upper end when the valveis released.

4. The disperser of claim 2 in which the air pressure means is a exiblebulb.

5. The disperser of claim 3 in which the air pressure means is aflexible bulb.

6. The `disperser of claim 3 in which the upper side of the piston andthe inside of the nozzle mouth each have sleeves coaxially positioned toeach other in spaced apart relationship and the spring means is a coilspring positioned externally of each of said sleeves.

7. A hand-transportable disperser for self-administering fine powderedmateria-ls to the respiratory system cornprising a mouthpiece portionessentially hollow internally and having a closed lower end portion andan open upper nozzle portion, a duct in the closed end portion leadingat the upper end from the hollow portion of the mouthpiece to airpressure means at the lower end for supplying air at supra-atmosphericpressure to the duct, means for holding a replaceable cartridge havingingress and egress holes and containing finely divided particles withthe said holes communicating with the duct, a valve comprising a pistonslidably mounted -inside the mouthpiece urged by spring means intosealing relationship `with the upper end of the duct, port hole means inthe mouthpiece leading to an open area 'beneath the piston so as toapply atmospheric pressure against the bottom of the piston, said springexerting pressure adequate to maintain the piston in ductsealingrelationship when air pressure is applied in the duct by the airpressure means, said spring exerting substantially less than atmosphericpressure against the piston so that a human, upon inhaling with themouthpiece nozzle in his mouth, lowers the air pressure above the pistonsufliciently for atmospheric pressure applied on the lower side of thepiston to overcome the spring pressure and displace the piston out ofsealing relationship with the duct thereby letting the air pressuremeans blow air through the cartridge and create a stream ofair-supported particles which is exhausted through the nozzle andinhaled into the respiratory system.

8. A hand-transportable disperser for self-administering line powderedmaterials to a human comprising a mouthpiece portion essentially hollowinternally and having a closed lower end portion and an open uppernozzle portion, a duct in the closed end portion leading at the upperend fnom the hollow portion of the mouthpiece to air pressure means atthe lower end for supplying air at supra-atmospheric pressure to theduct, means for holding -a replaceable cartridge having ingress andegress holes and containing iinely divi-ded particles with the saidholes communicating with the duct, passage means for diverting air fromthe lower portion ci the duct to the upper portion of the duct ywithoutpassing through the cartridge, a valve comprising a piston slidablymounted inside the mouthpiece urged by spring means into sealingrelationship with the upper end of the duct, port hole means in themouthpiece leading to lan open area beneath the piston so as to applyatmospheric pressure against the bottom of the piston, said springexerting pressure adequate to maintain the piston in duct-sealingrelationship when air pressure is applied in the duct by the airpressure means, said spring exerting substantially less than atmosphericpressure against the piston so that a human, upon inhaling with themouthpiece nozzle in his mouth, lowers the air pressure above the pistonsufficiently for atmospheric pressure applied on the lower side of thepiston to overcome the spring pressure and displace the piston out ofsealing relationship with the duct thereby letting the air pressuremeans blow part of the air through the cartridge thereby creating astream of air-supported particles which is exhausted through the egresshole of the cartridge to the upper part of the `duct where it isdispersed by the diverted air and propelled out the duct for furtherdispersion by air entering the port hole after which the air-supportedparticles are propelled out the nozzle portion and into the respiratorysystem of an inhaling person.

9. A disperser according to claim 8 in which the means for holding acartridge is for a cylindrical cartridge having the ingress and egressholes at the bottom and top respectively.

lO. A ydisperser for administering line powdered materials to a humancomprising a mouthpiece portion essentially hollow internally and havinga closed lower end portion and an open upper nozzle portion, a duct inthe closed end portion leading at the upper end rom the hollow portionof the mouthpiece to air pressure means for supplying air atsupra-atmospheric pressure to the lower end of the duct, means forholding a replaceable cartridge having ingress and egress holes andcontaining finely `divided particles with the said holes. communicatingwith the duct, a valve comprising a piston slidably mounted inside themouthpiece urged by sp1ing means into sealing relationship with theupper end of the duct, said pistonhaving a downwardly projecting skirtspaced away from the mouthpiece internal wall and extending intosubstantially sealing position with the inside of the closed end portionof the mouthpiece thereby form-ing an open area between the mouthpiecewall and the skirt wall, port hole means in the mouthpiece leading fromthe atmosphere to the `open area so as to apply atmospheric pressureagainst a minor portion of the lower side of the piston when the pistonis in sealing relationship with the duct, said piston having conduitmeans therethrough leading from the area surrounded by the skirt wallsto the mouthpiece nozzle portion, the spring exerting pressure adequateto maintain the piston in duct-sealing rel-ationship whensupra-atmospheric pressure is applied in the duct by the air pressuremeans, to a predetermined pressure, said spring exerting substantiallyless than atmospheric pressure against the piston so that a human, uponinhaling with the mouthpiece nozzle in his mouth, lowers the airpressure above the piston sufficiently for atmospheric pressure appliedon the said minor portion of the lower side of the piston to overcomethe spring pressure, displace the piston out of sealing relationshipwith the duct and displace the skirt from sealing contact with theclosed portion of the mouthpiece thereby permitting air to pass from theopen area to the area surrounded by the ski-rt walls so that atmosphericpressure is applied to substantially the enti-re bottom of the piston,and the air which goes through the conduit means in the piston furtherdisperses the stream of air-supported particles which is created whenair under pressure blows through the cartridge and out the duct upperend when the valve is released.

1l. `A hand-transportable disperser for self-administering fine powderedmaterials to a human comprising a mouthpiece portion essentially hollowinternally and having a closed lower end portion and an open uppernozzle portion, a duct in the closed end portion leading at the upperend from the hollow portion of the mouthpiece to air pressure means forsupplying air at superatmospheric pressure to the lower end of the duct,means for holding a replaceable cartridge having ingress and egressholes and containing 'finely divided particles with the said holescommunicating with the duct, passage means for diverting air from thelower portion of the duct to the upper portion of the duct Withoutpassing through the cartridge, a valve comprising a piston slidablymounted inside the mouthpiece urged by spring means into sealingrelationship with the upper end of the duct, said piston having adownwardly projecting skirt spaced away from the mouthpiece internalwall and extending into substantially sealing position with the insideof the closed end portion of the mouthpiece thereby forming an open areabetween the mouthpiece wall and the skirt Wall, port hole means in themouthpiece leading from the 'atmosphere to the open area so as to applyatmospheric pressure against a minor portion of the lower side of thepiston when the piston is in sealing relationship with the duct, saidpiston having conduit means therethrough leading from the areasurrounded by the skirt walls to the mouthpiece nozzle porti-on, thespring exerting pressure adequate to maintain the piston in ductsealingrelationship when supra-atmospheric pressure is applied in the duct bythe air pressure means, to a predetermined pressure, said springexerting substantially less than atmospheric pressure against the pistonso that a human, upon inhaling with the mouthpiece nozzle in his mouth,lowers the air pressure above the piston Suthciently for atmosphericpressure applied on the said minor portion of the lower side of thepiston to overcome the where it partially disperses the air-supportedstream of 10 2,642,063

particles being exhausted from the cartridges, and said stream ofdispersed particles is further dispersed as it blows through the conduitmeans in the piston due to mixing with air entering through the port.

References Cited in the le of this patent UNITED STATES PATENTS 464,969Ives Dec. 15, 1891 2,307,986 Bolte Jan. 1-2, 1943 Brown June 16, 1953UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent Nb..L2,992Y'645 i July 18 1961 Frank Fowler It ie hereby Certified that errerappears in the above numbered patent requiring correction and that thesaid Letters Patent should read as corrected below Signed and sealedthis 28th day of November*` 1961.

(SEAL) Attest:

ERNEST W. SWIDER DAVID L. LADD Commissioner of Patents Attesting OfficerU SCOM M DC

